Influenza A modification of endotoxin-induced otitis media with effusion in the guinea pig

Summary A total of 120 Hartley strain guinea pigs were used to investigate the possible role of influenza A in endotoxin-induced otitis media with effusion. Intratympanic inoculation of 0.2 ml physiologic saline solution containing 10⁴ plaque-forming units (PFU)/ml of influenza A suspension or 100 ng/ml lipopolysaccharide failed to induce either middle ear effusions or mucociliary pathologies in the tubotymapanum. In contrast, intratympanic inoculation 100 ng/ml endotoxin resulted in prolonged mucociliary dysfunction and middle ear effusions when 0.2 ml 10⁴ PFU/ml of influenza A was inoculated in the tympanic cavity. The inference is drawn that an influenza A infection might predispose the middle ear to endotoxin-induced otitis media with effusion.This paper was presented in part at the Fifth International Symposium on Recent Advances in Otitis Media in Ft. Lauderdale, Florida, USA, on 20–24 May 1991